Combined mercury interrupter and transformer



. T. AAMODT Feb. 29, 1944.

, COMB INED MERCURY INTERRUPTER AND TRANSFORMER Filed Oct. 16, 1940 INVENTOR By 7'. AAMODT 4 TTORNEY Patented Feta. 29,

UNITED STATES PATEM owing:

COMBINED MERGUE?! IKYEERRETPTEE TRANSFOREEEYZt Thoralf Aamodt, Annaciale, No 11, assignor to i Telephone Laboratories, Income York, N Y., a automation of Agzplication @ctoioer 194$, Seriai Nou 36:31AM

' 2 Claims.

This invention relates to mercury contaot ini iiiustrates a combined transformer terrupters and more particularly tocom'bined eiectromagneticaiiy operated mercury intern units consisting of one or more interrupter or switch structure mounting a plurality of switches associated with a transformer struccury interrupter switches the armatwres of which tore. 5 are adapted when operate to have different In a copending application Serial No 352,305 determined natural perioc of vibzati. filed in the name of 2, E :Eollarr; on October 19; 1940, a mercury contact interrupter @escriloeri and claimed in which a magnetic is vertically displaceabie in a magnetic itali alternately break and close a mercury oontact the field loeine provided by an electromagnet energiz intent" I; and ing circuit of which includes a tatkery, the mag- 1 M36 net winding, the normally closed. contacts oiti'ie oiisci c.

mercury switch anti the primary winding of a copending aoplication f transformer, the secondary of which supplies aiof a glass tube cont/a" r it ternating' current to an output mercury it in the bottom tiiereoi am, a oyl A feature of the present invention resides in ca}. armature 22 of magnetic material loose? combining in a single unit the functions or" pended therein by mea oi e, spr the electromagnet and the transformer and Q, aziapteo'; when to compile mounting the mercury switch in. sneie a man tween topand bottom lead her with respect to the core of the transfer er mercury anti wh caused to ris that when the switch contacts are the the influence a ma net;

field produced by current flowing 333i mary winding will cause the armature to be displaced. to open the circuit permitting t e armature to restore and reciose the sw tact which operation reoeat 7 termineci by the natural oi? of the armature, whereby a current n. at B cotenating character is produced in the seconciary tionec'i anti. arranges.

winding which may be utilized for the operation iliary or shunt gtiQ of telephone bells, electric motors source The interrupter s r of tone or for any other purpose where a subpositioneci oper core stantially constant i'reqnencysource is required. member 22, 3 1.2 su that A further feature resides in combining: a pin the individual armatures 2'13 of swi rality of switching units having differently tuneri slightly below center so that when t o armatures, with asingie transformer structu e former core 6 is energized flux: across whereby the selective closure of the primary cirbetween core extensions 2 and 3 tends i cuit through any one of the switches will gener 40 the armatures thereby breaking contact with t e ate an alternating current in the secondary mercury. Tl'ieoircuit for energizing t tr winding which corresponds to the natural peformer and operating the interrupt rind of the switch armature connected sir comprises a battery or other source of cuit,

rent 33, a winding s on the central leg; of Another feature of the invention resides in core, selecting keys Si, S2 S3 andEt and a specific structure for the switch armature c rre pondi in up I to a 02 w inwhich a sheet of magnetic material is formed 'upper terminals of which are connected to difinto a cylinder having a diametrically disierent portions of winding 9 for the purpose of posed partition to which an extension of the compensating for changes in impedance clue to upporting spring is axially fastened to extend 5 the difierent; frequencies of the interrupters as below the armature to contact with the mer-V determined by the natural periods of the din-er curyo ent armatures.

The invention will be understood from the fo1- A secondary or output winding it is also lowing description and accompanying drawing, in wound on the central leg of the transformer which: to which an output or work circuit it may be connected which work circuit may comprise differently tuned devices, such as telephone ringers which are to be selectively operated.

The operation of the interrupter transformer unit is as follows: Assuming that the armatures of switches la, lb, I c and l d are constructed to have natural vibration periods of 16 33 /3, 50 and 66 cycles per second, respectively, and that the telephone ringers l2a, l2b, I20 and l2d are each tuned to respond to a difierent one of these frequencies, 1. e., ringer l2a tuned to respond to a frequency of 16 cycles, l2b to 33% cycles, etc.

Now, if it is desired to actuate ringer 1211 key SI will be closed thereby completing a circuit from the source B over contacts of the key sl, mercury contacts of interrupter switch la, conductor l3, winding 9 of the transformer and back to the source B, whereupon a magnetic flux will be established across the air-gap and between the continues to repeat as long as key Si is closed at the predetermined rate, i. e., 16% vibrations per second. The alternately increasing and decreasing flux in the transformer core occasioned by interruptions of the circuit by switch la causes an alternating current of 16% cycles tobe induced in the secondary or output winding H! of the transformer which frequency flowing in the output circuit or line II will cause the correspondingly tuned ringer lZa to respond to the exclusion of the other three ringers which are tuned to other frequencies. Operation of any one of the other keys S2, S3 or S4 will cause the armatures of the corresponding interrupter switches to vibrate and actuate the correspondingly tuned ringers.

In accordance with a second feature of the invention a specific and improved structure for the armature 22 of the switches I a, lb, lo and Id is shown in Fig. 3, which armature is formed, from a single sheet of magnetic material, into a cylinder having a diametrically disposed partition 30 to which an extension 3| of the supporting spring 23 is axially fastened by means of punched lugs 32, 33, the extension memer 3| being carried below the cylinder to form a contact member 34 the lugs pressed down to hold the extension wire going operating cycle is repeated. This cycle 3| in position, following which the flat sheet is rolled into the cylindrical shape desired.

What is claimed is:

1. In a multifrequency generator in combination, an iron transformer core having an airgap therein and primary and secondary windings thereon, an output circuit connected to said secondary winding, a plurality of mercury contact interrupters each comprising a magnetic annature flexibly suspended and vertically movable within a sealedvessel having a pool of mercury at the bottom, each of said armatures having a different predetermined natural period of vibration, a member connected to and movable with each armature normally in contact with the mercury at the bottom of the respective vessel, magnetic extension members for said core formed to provide a secondary air-gap in parallel with said first air-gap and to support said plurality of interrupter vessels irisuch a position that the armatures thereof in their normal position partially shunt the secondary air-gap formed by said extension members, a source of direct current and selective means for connecting said source and the primary winding in series with any one of said mercury contacts, whereby said core is energized to move the armature of the interrupter, associated with the connected mercury contacts, into a position to break the contact and deenergize the core thus permitting the contacts to reclose and reenergize the core which cycle is repeated at the rate predetermined therefor, during the interval the source is connected.

rality of scaled vessels each containing a pool of mercury in the bottom, vertically supported in said openings, each of said vessels also containing a magnetic armature flexibly supported and vertically movable therein and tunedto have a characteristic natural period of vibrations different from the others, a contact member connected to and movablewith each of said armatures and normally contacting the respective pool of mercury, said vessels being so positioned in said aligned openings that each armature in its normal position partially, but not completely, shunts said secondary air-gap, a source of direct current, and means for connecting said source in circuit with said primary winding over any one of said mercury contacts.

'I'HORALF' AAMODT. 

